Dropout Spacing, Axle Spacers and Hubs for Old Bikes

I was talking with Jeff about his new Sekine project the other day, and he was curious about how to fit wheels into this old frame — he had tried a modern set of wheels off his road bike, and the hub was way too wide to fit between the dropouts.

I told him that I was having a related problem with an old bike that I resurrected. In my case, though, I had a hub that fit just fine between the dropouts, but I had to add axle spacers to “build out” the proper “over-locknut dimension” (O.L.D.) so everything fit properly. Over time, though, I found out that my axle spacers were causing me some problems. I had some old 1mm thick axle spacers in my spare parts boxes, and they were no longer viable — they were warped or something, so I couldn’t adjust an excessive amount of play out of my rear hub bearings…I decided to remove them and reset my frame’s dropout spacing to fit the “native” 120mm O.L.D.

The culprits: old axle spacers that were no longer flat, causing excessive play in the bearings.

Old axle spacers

To respace a frame, you will need a length of threaded rod (“allthread”), some large washers and nuts to fit the rod, and an accurate metric ruler or precision calipers. I used 3/8″ allthread since it was closest to the diameter of the hub axle I am using.

Start out by taking the rear wheel out of the frame and measuring the dropout spacing from the inside face to the opposite inside face, like so:

Measuring dropout spacing

Here, it shows a spacing of 126mm. The second step is to insert the allthread and washers into the dropouts as shown below:

Allthread ready to push those chainstays together!

Simply crank on the nuts with an appropriate wrench — and do it evenly…a half-turn on each side at a time so everything stays aligned. Remove the allthread and washers periodically to check your progress. You may have to go pretty far past your “target” width so the chainstays and dropouts finish off at the appropriate distance. I squeezed my frame down to about 105mm before the respacing “took”, leaving me with a perfect 120mm spacing. Once the axle spacers were removed from my hub, I was able to get rid of the bearing play and everything was rock-solid once again!

Want to spread out your rear triangle rather than squeezing it down? Simply install the allthread with the washers on the INSIDES of the dropouts and twist those nuts accordingly.

I should add at this point that this method only works with steel frames. While it can be done to a certain degree with an aluminum bike frame, I don’t really recommend it — if you only have to squeeze or spread the dropouts a couple millimeters, it’s probably OK to use this method on an aluminum frame. DO NOT attempt this method on a carbon frame, though, unless you really want to break something!

For Jeff’s application, I think a “flip-flop” hub might be a perfect solution — plenty of room on the axle for proper spacers, if needed (just buy NEW spacers that you know are flat!), and room for a 5 or 6-speed cluster on the freewheel side of the hub.

The other thing Jeff wanted to do was go from the Sekine frame’s native 27″ wheels down to a more modern and versatile set of 700c wheels. Going to 700c wheels is better in the long run because there is much better availability of tires and rims for this size.

Doing the swap is easy enough to do, since 700c wheels are a bit smaller in diameter and will easily fit into such a frame. The one sticking point, though, might be finding brakes that have enough “reach” to work with the new, smaller wheels. Sheldon Brown offers a kludgy, but acceptable brake drop method, but I think it is a bit more elegant to find appropriate long-reach brakes…Ebay might be a good source, or you could always go for a modern set of Tektro long-reach badboys.

I want to add in a plug for fellow Floridians and master wheel builders For about $100 or so, you can buy a handbuilt, rock-solid set of wheels. I went for their bottom-shelf 700c flip-flop set with Formula hubs on Weinmann rims…not expecting too much, but I can say that I’ve BEAT on these wheels: rolling down stairs, riding on 2 miles of cobblestones every day that I commute, etc. The wheels are still as true as the day they came in the mail!

So, get out there and tinker…there’s lots of good stuff you can do right at home to bring an old frame back to life, even with more modern components!


  1. RL Policar

    No that is super cool! I do like your warning about the carbon. 🙂

  2. Ghost Rider

    Allthread is your friend! It can be used for lots of bike-related chores…pressing in headsets, pressing in sealed bearing cartridges, “cold setting” frames, etc…and it is way cheaper than the comparable Park Tools!

  3. Val

    Jack: Don’t forget to check the alignment of the rear triangle once you’re done. Tie a string to the right rear dropout, stretch the string around the head tube and back to the left rear dropout, and tie it so that it is nice and taut. Now measure the distance between the seat tube and the string on each side of the seat tube. The distances should be identical. This will tell you whether the rear triangle is lined up with the front triangle, which can be important. It is also worthwhile to make sure that the dropouts are parallel, which you can do by turning the frame on its side and using a spirit level on each dropout. Have fun!

  4. Ghost Rider

    Yes, excellent additions! Turning the two sides an equal amount seems to keep things aligned, but the dropout alignment can definitely be thrown off — better to check it like Val says and correct as needed with a large adjustable wrench.

  5. Val

    In theory, equal pressure should move the dropouts in equally, but in practice, the stays may have different strengths or stifnesses due to different shapes, inconsistent heating during the building process, or past damage. Not only that, but the frame may have been off center to begin with – always best to check before building up, while you still have a chance to correct things. Saves time and trouble, you know?

  6. Jeff Rossini

    Val, it sounds like I might need to recruit you to help out with this project at some point. Do you ever go to the Bike Saviours?

  7. Val

    Jeff: Not yet; are they in the Seattle area?

  8. Jeff Rossini

    Ahh, sadly they are not; it is a Tempe local thing only. For some reason I got the impression that you lived in Phoenix. Blast!

  9. Ghost Rider

    Jeff…don’t give up — the process, even with string-checking, isn’t hard at all. It’s a little tedious, to be sure, but well within the capabilities of even the most ham-fisted home mechanic (such as myself)!

  10. Pingback: Just Ask Jack -- Modern Shifting on a Classic Bike? | Bike Commuters

  11. Pat Harrison

    Thanks for the advice on cold setting using threaded rod, which seems less brutal than the lump of timber you swing on, that Sheldon mentioned. I imagine either will work; none the less, yours seems more civilised! I have an old French bike I want to use modern spare parts with. May I pick your brains? Have you any experience of threadless bottom brackets? The original is for cottered cranks and features two right hand threaded bearing cups.
    Thanks for any help, Pat Harrison

  12. Ghost Rider


    by all means, ask away — either here or via email at “ghostrider(at)bikecommuters(dot)com”.

    My only familiarity with threadless BBs are the old Mavic and the newer YST cartridge models. The Mavic one requires a special chamfering tool to cut tapered faces in the outer edges of the bottom bracket shell…and most shops don’t have that special tool. The YST model doesn’t require such chamfering, as far as I know.

  13. Pat Harrison

    Thanks. We’ll see how it goes with YST. I got the frame and bits separated, sticking my tongue out as I sorted which way the bottom bracket unscrewed. Wrecking something old is always difficult. Some prat comes along and says it’s such a pity they don’t make stuff like that anymore. One feels obliged to look sad and agree, although deep down one is thinking,’Thank God!” Could anyone actually prefer a Preston Tucker to a VW Golf? That comment may generate more hate-mail than I bargained for.

  14. Wheel Hub Bearing

    Very helpful article and good comments.

  15. Mike

    Using the ‘All thread’ and adjusting the rear dropouts by turning nuts equally will not necessarily move each droput equally. Regardless of which nut you turn the rear stay that is weakest will be the one that deforms, so care must be taken to ensure that the rear triangle is still centred. There is also the possibility of overstressing the butted joints of the bottom bracket assembly rather than bending the stay tubes.

    I should add that I’m a professional stress engineer.

  16. Ghost Rider

    Yes, alignment should always be checked after cold-setting a frame. Cranking the two opposing nuts evenly sure does help with keeping things straight, however…but I double-check that and the derailleur hanger alignment when I’m done.

  17. Tracy

    Thank you so much for writing this blog. I’ve been going crazy thinking there was something wrong with the fork on my old bike frame I just got cause the old wheel fit in just fine, but the hub on the new wheel is nearly .5 cm too big! I’m still going to check if its bent, but this makes me feel less crazy. I’m still learning, here.

    But really, thanks!

  18. Philip

    I recently bought an old frame for bike build, and I am thinking about using this method. Do you think I can do this on the fork as well? It needs to be widened a few mm.

  19. Ghost Rider

    Philip, it depends on the fork and what it is made of, but generally the answer is “no” — much better to find a suitable replacement fork. Any bending or deflection of the original fork blades can be a dangerous proposition.

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